Investments (Maturity Distribution) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale, Amortized Cost
Due in one year or less	$ 13,425
Available-for-sale Securities, Debt Maturities, Due After One Year Through Five Years, Amortized Cost Basis	136,629
Available-for-sale Securities, Debt Maturities, Due After Five Years Through Ten Years, Amortized Cost Basis	276,325
Available-for-sale Securities, Debt Maturities, Due After Ten Years, Amortized Cost Basis	965,201
Debt Securities, Available-for-sale, Amortized Cost	1,391,580	$ 1,389,038
Debt Securities, Available-for-sale, Fair Value
Due in one year or less	13,375
Available-for-sale Securities, Debt Maturities, Due After One Year Through Five Years, Fair Value	137,256
Available-for-sale Securities, Debt Maturities, Due After Five Years Through Ten Years, Fair Value	277,228
Available-for-sale Securities, Debt Maturities, Due After Ten Years, Fair Value	845,638
Fixed maturity securities, available-for-sale	$ 1,273,497	$ 1,238,981

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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